IIRC, TESCO is BP or Esso, Sainsbury's is Shell, not sure about Morrisons.

I imagine they are. To the best of my knowledge Tesco doesn't own a refinery. Hence a certain amount of sceptism on my part.

I used to work for a food company and we had products where people swore blind that one "premium" brand was massively better than another "budget" brand and you could clearly taste the difference. Thing is we changed the budget formula to that of the premium brand as it reduced stock keeping units and costs overall so they were the same but with a different label.

Stanlow refinery in Ellesmere Port, has Shell, Tesco , Morrisons, and dhl, along with many other tankers all filling up there, its when it goes in the underground tank or in the tanker they add an additive if they can be bothered , also does shell v power and texaco excellium actually do anyhing.

project - Member
Stanlow refinery in Ellesmere Port, has Shell, Tesco , Morrisons, and dhl, along with many other tankers all filling up there, its when it goes in the underground tank or in the tanker they add an additive if they can be bothered , also does shell v power and texaco excellium actually do anyhing.

Filled up tonight with ESSO, and a big difference in performance.

Careful, this can be a false impression. Differences in fuels (particularly the RON rating) can cause the car to run differently until (in most modern cars) the ECU is abe to adjust the mix to the engines designed tolerance / preference.

Some performance engines (Subaru & BMW are an example) are designed to run on higher rated fuel for max performance, but cope adequately on your standard fuels.

Do some dedicated testing and you may find that after a week or so (dependant on mileage) you car will manage the same MPG and be putting out similar BHP of you have merely swapped Shell unleaded & esso unleaded.

Which mag did a test BTW that concluded for the majority of motorists, "Super unleaded" fuels were a greater expense ratio than they were a saving on MPG or increase on power - simply not worth the extra money.

At the refineries when the different fuel tankers load up is when the various additives are added, these are through machines/pumps that dose automatically to a certain spec whilst loading, this is determined by the companies requirement that is purchasing the fuel eg supermarket fuels are to a cost so use less additives and BP etc dose higher or with more additives. There is a reason supermarket fuel is cheaper that is it or they have a reduced margin to work to.

A friend of mine worked at the Shell refinery for a while a few years ago. All the base fuels are the same and it's then the additives that are added that make the difference. Then the supermarket fuels were just a couple of generations back from the premium ones in terms of what is added.

both myself and my wife both drive cars with vw diesel engines, as hers is a company car she always puts supermarket fuel in it. I always use shell (have the points card) both cars are of a similar age and on similar miles (90k ish)
my wife has needed 2 egr valves and one system reset in that time due to poor fuel, i have had no problem whatsoever. i wouldnt buy supermarket fuel for a car i owned...

Fifth gear did a prog on super unleaded. Result more performance biased your motor the bigger the bhp improvement.
I have a remapped golf turbo, the ECU adjusts the engine management for the fuel used (knock sensor & pre-ignition)and the difference inusing super unleaded is plainly obvious.
Novelty wears off and back to Asda you go!!

I bought a Mercedes C220 diesel new in December 2007 and have 99% of the time filled up with supermarket fuel. The car has now done about 70k miles and passed two MOT's with no issues and never missed a beat. The car has always been serviced by MB when required returns more MPG than ever before.

Not personally convinced all the negative talk about supermarket fuel can be fully justified.

Tesco fuel has 5 % ethanol in it dont it ? Ethonol has a lower calorific value

I get about 50-60 miles per tank consistantly when i swap between fuel suppliers - tesco gets about 450 and shell is about 500ish - and thats with brimmed tanks unfortunantly there are ery few fuel suppliers up here its all supermarkets which sucks

Since starting work in 1981 I've always been close to a Tesco fuel station, so 99% of the fuel I've used over the last 30 years has been supermarket. Over loads of cars (cheap, slow and fast, but all petrol) I've never had problems with fuel systems, carbs or injectors.
In no way scientific, but still interesting.